CEE Industrial Extension Plugs Selection Guide
When selecting IEC 60309 CEE extension plugs, compare 16 A–125 A current, 3/4/5 poles, blue (230 V) vs red (400 V) voltage coding and IP44/IP67 sealing.
This guide explains what to look for when choosing products in the CEE Extension Plugs category for portable industrial machinery, construction site leads, welding equipment and shore/caravan power cords.
Rated current (16 A, 32 A, 63 A, 125 A) and pole configuration (3P, 4P, 5P)
Under IEC 60309, plug diameter varies by both amperage and pole count, preventing mismatched connections:
- 3-Pole (2P+E / 1P+N+E): Blue housing, 230 V AC single-phase (6h earth clock position) for site tools, caravans and marinas.
- 4-Pole (3P+E): Red housing, 400 V AC three-phase without neutral (6h) for pure three-phase motors, pumps and welders.
- 5-Pole (3P+N+E): Red housing, 400 V AC three-phase with neutral (6h) for machinery and sub-distribution boxes requiring both 400 V and 230 V.
IP44 splash-proof vs IP67 watertight locking ring
Standard indoor factories use IP44 splash-proof plugs. For outdoor construction sites, washdown areas, tunnels and marine docks, specify IP67 watertight plugs equipped with a threaded bayonet locking ring.
CEE extension plug comparison table
| Selection Criterion | 3-Pole (2P+E — Blue 230 V) | 4-Pole (3P+E — Red 400 V) | 5-Pole (3P+N+E — Red 400 V) |
|---|---|---|---|
| Pin Layout | Line + Neutral + Earth (6h clock position) | 3 Phases + Earth — No Neutral (6h) | 3 Phases + Neutral + Earth (6h) |
| Current Ratings | 16 A, 32 A, 63 A | 16 A, 32 A, 63 A, 125 A | 16 A, 32 A, 63 A, 125 A |
| Sealing & Features | IP44 or IP67 bayonet ring; screw/spring clamp | IP44 or IP67; pilot contact on 63 A & 125 A | IP44 or IP67; optional phase-inverter pins |
| Typical Application | Caravans, boats, single-phase site tools | 3-phase motors, pumps & welders without neutral | CNC machines, combination boxes, mobile compressors |
Frequently asked questions
How do I avoid confusing 4-pole (3P+E) and 5-pole (3P+N+E) CEE plugs?
Count the total brass pins inside the plug shroud (including the thicker earth pin): a 4-pole (3P+E) plug has 4 pins total (no neutral), whereas a 5-pole (3P+N+E) plug has 5 pins total. A 4-pole plug will not fit into a 5-pole socket.
What is a phase-inverter CEE extension plug?
When a portable three-phase pump or compressor spins backward after being plugged into a new outlet, a phase-inverter plug lets you rotate two phase pins 180° with a screwdriver to correct phase rotation without opening the plug housing.
What does the smaller center pin (pilot contact) do on 63 A and 125 A plugs?
The shorter pilot pin breaks first when the plug is withdrawn, signaling an upstream contactor to drop out the load before the main power pins separate under high current.